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研究了LY12CZ铝合金在EXCO溶液中的自腐蚀电位和最大腐蚀深度随浸泡时间的变化关系.结果表明、LY12CZ铝合金在EXCO溶液中的腐蚀动力学可分为两个阶段:浸泡前期,腐蚀发展较快,但腐蚀动力学的规律性不明显;浸泡后期,腐蚀发展稍慢,腐蚀动力学近似地遵循线性规律.其自腐蚀电位的变化经历了一个先正后负的过程,浸泡前其自腐蚀电位随浸泡时间的延长而正移;浸泡后期自腐蚀电位随浸泡时间的延长而近似地按指数规律负移.自腐蚀电位和最大腐蚀度之间存在着对应关系,通过自腐蚀电位的测量,可以推测最大腐蚀深度,从而能比较有效地预测LY12CZ铝合金在EXCO溶液中的腐蚀损伤.“,”Maximum corrosion depth measurement can evaluate corrosion damage of aluminum alloy precisely.Unfortunately, this kind of method is destructive. To find a non-destructive and in situ method which canbe used as praictical and accelerated corrosion test, an electrochemical method-free corrosion potentialmeasurement was developed. EXCO test was carried out according to HB 5455 staridard. Free corrosionpotential and maximum corrosion depth of LY12CZ aluminum alloy were measured. The kinetics law ofthe aluminum alloy corroded in EXCO solution can be divided into two segments. In the earlier stage itscorrosion rate is faster while in the later stage it becomes slower and keeps constant. Fres corrosion potentialof the alloy increases with immersion time at first, and then decreases exponentially. The relationshipsbetween fres corrosion potential and maximum corrosion depth of the aluminum alloy was established.Where D is the maximum corrosion depth, E is the free corrosion potential and t is immersion time. Thusby measuring the free corrosion potential of LY12CZ aluminum alloy) the maximum corrosion depth canbe evaluated and its corrosion damage can be predicted.